Cross-compiling for the RaspberryPi
From AIRWiki
This page will guide you to setup a complete cross-compiling environment for the RaspberryPi board. This procedure is tailored for and tested on Ubuntu 12.10, but it can be easily adapted for the use on other distributions.
Contents
Prerequisites
- Install all the required software packages:
sudo apt-get install git rsync cmake
- If you are using a 64-bit version of Ubuntu, also install the 32-bit compatibility libraries:
sudo apt-get install ia32-libs
- If you are using a 64-bit version of Debian, the ia32-libs metapackage is no longer installable. Execute instead
su -
dpkg --add-architecture i386
apt-get update && apt-get install libc6-i386 lib32stdc++6 zlib1g:i386
- The guide will take for granted that you are using the official Raspbian OS image, downloadable from the RaspberryPi website.
- Moreover, you will need a working SSH connection between the Raspberry and your computer (not covered by this guide).
Step One: installing the cross-compiler
- Select a directory in which you will install everything. For the purposes of this guide, I will consider a subdirectory of your home folder,
~/raspberrypi. Create it and then access it:
cd
mkdir raspberrypi
cd raspberrypi
- Download the "official" cross-compiler of the Raspberry Pi project through
git:
git clone git://github.com/raspberrypi/tools.git
This will create, among other things, a tools/arm-bcm2708 subfolder containing three different compiler toolchains:
arm-bcm2708-linux-gnueabi
arm-bcm2708hardfp-linux-gnueabi
gcc-linaro-arm-linux-gnueabihf-raspbian
We are going to use the third of these toolchains, since it's the most optimized and supports the FPU that is available on the RaspberryPi board.
- Go back to your home directory, and open your
.bashrcconfiguration file with any text editor, likenano,geditorleafpad, and add this string at the bottom:
PATH=$PATH:$HOME/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin
- Now, either logout and login back again, or just close and reopen the terminal window, and type:
arm-linux-gnueabihf-gcc -v
If all goes well, you should see something like
tudhalyas@gondor:~$ arm-linux-gnueabihf-gcc -v
Using built-in specs.
COLLECT_GCC=arm-linux-gnueabihf-gcc
COLLECT_LTO_WRAPPER=/home/tudhalyas/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/../libexec/gcc/arm-linux-gnueabihf/4.7.2/lto-wrapper
Target: arm-linux-gnueabihf
Configured with: /cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/src/gcc-linaro-4.7-2012.08/configure --build=i686-build_pc-linux-gnu --host=i686-build_pc-linux-gnu --target=arm-linux-gnueabihf --prefix=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/install --with-sysroot=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/install/arm-linux-gnueabihf/libc --enable-languages=c,c++,fortran --disable-multilib --with-arch=armv6 --with-tune=arm1176jz-s --with-fpu=vfp --with-float=hard --with-pkgversion='crosstool-NG linaro-1.13.1+bzr2458 - Linaro GCC 2012.08' --with-bugurl=https://bugs.launchpad.net/gcc-linaro --enable-__cxa_atexit --enable-libmudflap --enable-libgomp --enable-libssp --with-gmp=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-mpfr=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-mpc=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-ppl=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-cloog=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-libelf=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-host-libstdcxx='-L/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static/lib -lpwl' --enable-threads=posix --disable-libstdcxx-pch --enable-linker-build-id --enable-plugin --enable-gold --with-local-prefix=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/install/arm-linux-gnueabihf/libc --enable-c99 --enable-long-long
Thread model: posix
gcc version 4.7.2 20120731 (prerelease) (crosstool-NG linaro-1.13.1+bzr2458 - Linaro GCC 2012.08)
Step Two: set-up your compiling environment
- Go back into the
raspberrypidirectory and create a subfolder namedrootfs:
cd
cd raspberrypi
mkdir rootfs
- Now tell
rsyncto copy the entirety of the/usrand/libdirectories of your RaspberryPi filesystem into the newly created folder on your computer:
rsync -rl --delete-after --safe-links pi@$RASPI:/{lib,usr} $HOME/raspberrypi/rootfs
where $RASPI is the IP address of the Raspberry. You can put this line of code in a text file and save it as a shell script for your convenience.
- Create a text file called
Toolchain-RaspberryPi.cmakeand insert the following into it:
SET(CMAKE_SYSTEM_NAME Linux)
SET(CMAKE_SYSTEM_VERSION 1)
# specify the cross compiler
SET(CMAKE_C_COMPILER $ENV{HOME}/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-gcc)
SET(CMAKE_CXX_COMPILER $ENV{HOME}/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-g++)
# where is the target environment
SET(CMAKE_FIND_ROOT_PATH $ENV{HOME}/raspberrypi/rootfs)
# search for programs in the build host directories
SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
# for libraries and headers in the target directories
SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
- Now you are able to compile your own projects using
cmake, by passing the path of the Toolchain specification file to the program (supposing that the sources are located into asrcdirectory which in turn is located into${PROJECT_DIR}):
mkdir ${PROJECT_DIR}/build
cd ${PROJECT_DIR}/build
cmake -G"Eclipse CDT4 - Unix Makefiles" -D CMAKE_BUILD_TYPE=Debug -D CMAKE_TOOLCHAIN_FILE=$HOME/raspberrypi/Toolchain-RaspberryPi.cmake ../src
Step Three: Remote program execution through Eclipse
... to be continued ...
